Diurnal Temperature Fluctuation Impact on Transcriptomic Profile in V. vinifera L. 'Reisling' and 'Cabernet Franc'

The influence of temperatures on dormant bud gene expression was analyzed during an eighteen-day period in January 2016 (January 14th to 31st) when daily temperatures ranged between 13 ºC and -15 ºC. This study collection period captured three different natural consecutive temperature events that fluctuated above and below 0 ºC or remained constantly below 0 ºC. Dormant buds were collected from two different wine grapevine cultivars, Cabernet Franc’ and ‘Riesling’.

The buds were collected from Ravines Wine Cellar vineyards in Geneva, New York (42.843898, -77.003488. There were two 84-hour diurnal cycles (DC) that included temperatures fluctuating above and below 0 ºC (DC1: Jan 14 to Jan 17; DC2: Jan 24 to Jan 27) (Figure 1, Table 1). In DC1 and DC2, samples were collected 3 times/day, during the dark periods (6:00 and 18:00) and once in the light at warmest part of the day (14:00).